Melbourne University venom researcher Bryan Fry said early analysis of the venom collected from 203 octopuses in 2008 had revealed that Antarctic octopus venom harboured a range of toxins, two of which had not previously been described.

''We found molecules with structures that are unlike anything we have ever seen before. And if we can understand how it works, we can harness it because here is a natural anti-freeze venom,"' said Dr Fry, who led the research team.

The ability of the enzymes in the venom to continue functioning in freezing waters could have a range of applications for humans - from drug development to cold-water washing detergents. The surface temperature of Antarctic waters is about minus 2 to minus 4 degrees, but some of the octopuses were found more than a kilometre below the surface where the waters would have been much colder.

New species discovered
The researchers - from Melbourne University, the Norwegian University of Technology and Science and the University of Hamburg - have also revealed the existence of four new, and as yet unnamed, species of octopus.

''On the genetic tree, they don't fit with any of the described species, and one of them is so divergent that it will actually be a new genus,' ' Dr. Fry said

Collected over six weeks in the east Antarctic in 2008 as part of a census on Antarctic marine life, the octopuses were DNA typed.

The findings are published in the British journal Toxicon this month.